SPEED AND ROTOR POSITION ESTIMATION OF ELECTRICAL MACHINES USING ROTOR SLOT HARMONICS OR HIGHER ORDER ROTOR SLOT HARMONICS

摘要

The present invention is a method and a system developed for speed and rotor position estimation of electrical machines. In this invention, rotor slot harmonics are detected either from the motor current or voltage or voltage induced on an external search coil or by similar means. The excitation frequency component of the signal used is eliminated; rotor slot harmonics are extracted from the resulting signal via demodulation. Rotor speed and position is obtained by processing the rotor slot harmonic variation in real time; and this process does not employ any spectral analysis technique.